SIST EN 2924:2019

Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated, left hand thread - Classification: 600 MPa (at ambient temperature) / 425 °C

This document specifies the characteristics of hexagon plain nuts, reduced height, reduced across flats, with left hand thread, in heat resisting steel, silver plated.
Classification: 600 MPa /425 °C.

Luft- und Raumfahrt - Flache Sechskantmuttern, kleine Schlüsselweite, aus hochwarmfestem Stahl, versilbert, Linksgewinde - Klasse: 600 MPa (bei Raumtemperatur) / 425 °C

Série aérospatiale - Écrous hexagonaux ordinaires, hauteur réduite, surplats réduits, en acier résistant à chaud, argentés, filetage à gauche - Classification: 600 MPa (à température ambiante) / 425 °C

Aeronavtika - Matice, šestrobe, drsne, z zmanjšanim zevom ključa, iz toplotnoodpornega jekla, posrebrene, levi navoj - Klasifikacija: 600 MPa (pri okoljski temperaturi)/425 °C

Ta dokument določa lastnosti šestrobih drsnih matic zmanjšane višine, z zmanjšanim zevom ključa, z levim navojem, iz toplotnoodpornega jekla, posrebrenih.
Klasifikacija: 600 MPa/425 °C.

General Information

• Status: Published
• Publication Date: 14-Apr-2019
• ICS: 21.060.20 - Nuts
• ICS: 49.030.30 - Nuts
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 11-Apr-2019
• Due Date: 16-Jun-2019
• Completion Date: 15-Apr-2019
• Ref Project: EN 2924:2019 - Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated, left hand thread - Classification: 600 MPa (at ambient temperature) / 425 °C

Overview

SIST EN 2924:2019 is a European standard developed by the Aerospace and Defence Industries Association of Europe (ASD-STAN) and approved by the European Committee for Standardization (CEN). It specifies the requirements for aerospace-grade hexagon plain nuts with reduced height and reduced across flats, made from heat-resisting steel with silver plating. These nuts feature a left-hand thread, designed to operate reliably at elevated temperatures up to 425 °C with a mechanical strength classification of 600 MPa at ambient temperature. The standard ensures uniformity, safety, and performance in critical aerospace applications, where reliable fastener performance under extreme conditions is essential.

Key Topics

• Nut Configuration and Dimensions
  SIST EN 2924:2019 details the specific dimensions, reduced height, and reduced flats configuration for hexagon plain nuts, ensuring compactness and weight reduction without compromising mechanical integrity.

• Material Specification
  The nuts are manufactured from heat-resisting steel, capable of withstanding maximum service temperatures of 425 °C without permanent degradation, critical for aerospace thermal environments.

• Surface Treatment
  The standard mandates silver plating on nuts, with thickness specifications between 5 µm to 15 µm on external surfaces and a minimum of 5 µm on the pitch diameter, improving corrosion resistance and conductivity.

• Mechanical Performance
  Classified for a minimum tensile strength of 600 MPa under ambient conditions, ensuring high mechanical robustness for aerospace fastening needs.

• Left Hand Thread
  Designed with left-hand threading, which is often used to prevent loosening in specific aerospace assemblies subjected to rotational forces.

• Marking and Designation
  Nuts are marked according to EN 2424 with style C plus the “MJ” identification, enabling traceability and compliance verification.

• Compliance and Quality Assurance
  Manufacturers must comply with ISO 9139 for technical specifications and EN 9100 quality management standards for aerospace, space, and defense organizations.

Applications

• Aerospace Fastening Systems
  EN 2924 nuts are ideal for assembly in aircraft and spacecraft where elevated temperature resistance, strength, and compact size are crucial.

• Engine and Thermal Systems
  Used in high-temperature zones such as turbine engines, exhaust assemblies, and other aerospace components exposed to intense heat.

• Vibration-Prone Environments
  The left-hand thread and precise manufacturing tolerances help maintain joint integrity in vibration-intensive aerospace applications.

• Lightweight Structural Components
  Reduced height and across flat dimensions contribute to weight savings, benefiting overall aircraft fuel efficiency and performance.

• Corrosion and Wear Resistance
  Silver plating ensures protection against oxidation and wear in harsh environmental conditions commonly experienced in aerospace operations.

Related Standards

• EN 2424 – Aerospace series: Marking of aerospace products, providing guidelines for product identification and traceability.

• EN 2786 – Aerospace series: Electrolytic silver plating of fasteners, specifying processes and controls for surface coating quality.

• ISO 5855-2 – Aerospace: Limit dimensions for bolts and nuts with MJ threads, supporting dimensional compatibility.

• ISO 8788 – Aerospace: Tolerances of form and position for metric nuts, ensuring geometric precision.

• ISO 9139 – Aerospace: Procurement specification for plain or castellated nuts, covering technical requirements and manufacturing control.

• EN 9100 – Quality management systems for aviation, space, and defense organizations, essential for aerospace manufacturing compliance.

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SIST EN 2924:2019 establishes a high standard for hexagon nuts used in aerospace applications, combining strict mechanical properties with temperature resistance and surface protection. It supports manufacturers and engineers in selecting reliable fasteners that meet stringent aerospace industry regulations, enhancing safety and performance in demanding environments. This standard is fundamental for ensuring fastening quality in critical components where failure is not an option.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2019
Aeronavtika - Matice, šestrobe, drsne, z zmanjšanim zevom ključa, iz
toplotnoodpornega jekla, posrebrene, levi navoj - Klasifikacija: 600 MPa (pri
okoljski temperaturi)/425 °C
Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat
resisting steel, silver plated, left hand thread - Classification: 600 MPa (at ambient
temperature) / 425 °C
Luft- und Raumfahrt - Flache Sechskantmuttern, kleine Schlüsselweite, aus
hochwarmfestem Stahl, versilbert, Linksgewinde - Klasse: 600 MPa (bei
Raumtemperatur) / 425 °C
Série aérospatiale - Écrous hexagonaux ordinaires, hauteur réduite, surplats réduits, en
acier résistant à chaud, argentés, filetage à gauche - Classification: 600 MPa (à
température ambiante) / 425 °C
Ta slovenski standard je istoveten z: EN 2924:2019
ICS:
21.060.20 Matice Nuts
49.030.30 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 2924
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2019
EUROPÄISCHE NORM
ICS 49.030.30
English Version
Aerospace series - Nuts, hexagon, plain, reduced height,
reduced across flats, in heat resisting steel, silver plated,
left hand thread - Classification: 600 MPa (at ambient
temperature) / 425 °C
Série aérospatiale - Écrous hexagonaux ordinaires, Luft- und Raumfahrt - Flache Sechskantmuttern, kleine
hauteur réduite, surplats réduits, en acier résistant à Schlüsselweite, aus hochwarmfestem Stahl, versilbert,
chaud, argentés, filetage à gauche - Classification: 600 Linksgewinde - Klasse: 600 MPa (bei Raumtemperatur)
MPa (à température ambiante) / 425 °C / 425 °C
This European Standard was approved by CEN on 15 July 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 2924:2019 E
worldwide for CEN national Members.

Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Required characteristics . 4
5 Designation. 8
6 Marking . 8
7 Technical specification . 8

European foreword
This document (EN 2924:2019) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical
...